Gun turret



av. 27, 145. ca. w. PONTIUS, 30., ETAL 2,389,997

GUN 'I'URRET Filed Aug. 19, 1941 s Sheets-Sheet 1 INVENTOR.

6502 M Fwy/05 BYFOYQL J Patented Nov. 27, 1945 GUN TUB/BET George W. Pontlus, III, and Royal .7. Beck, South Bend, Ind., asslgnors to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application August 19, 1941, Serial No. 407,468

9 Claims.

This invention relates to gun turrets and particularly to turrets of the retractable type adapted for use in aircraft. Such a turret is described in Pontius application, Serial No. 391,911, filed May 5, 1941.

movements.

tion.

tion.

ing drawings, in which:

ative position;

movements latch mechanism; and

ing this invention.

ment of the turret are shown in diagrammatic form in Figure 3 wherein the turret is shown in an extended position. The turret I02 is supported on a four-armed spider II which is secured to structural members such as I I5 01' an More particularly the invention relates to imairplane and which has a central collar IIB. Ball provements in retractable turrets, and includes bearings such as II8 rotatably support an inmeans for effecting retraction and rotative moveternally threaded sleeve I20 within collar IIB, ment of such a turret, and comprehends the use which sleeve has an upper ring gear portion I22. of a single motor with said means to effect such A threaded column I25 is threaded into sleeve An important feature contemplates I20 and is thereby supported within spider III. the prevention of rotative movement of such a A head unit I26 rotatably rides on the upper end turret until it has extended to the operating posiof column I24 and is itself restrained from rotation by a telescoping yoke member I28 secured It is, therefore, an object to provide a mechato the outer end of one arm of spider I It, nism whereby a single power unit can selectively A single power source is used to rotate the retract the turret or rotate it in azimuth. sleeve I in order to rotate the turret in azi- It is another object to provide retracting means muth or optionally to retract and extend the turfor a turret mounted on a single central column. ret. This power source is an electric motor I30 It is another object of our invention to provide 20 suitably secured to the spider H4. The motor a novel latch mechanism for connecting the cen- I30 drives a motor shaft I30 to which is secured tral column of a turret selectively to a rotatable a worm screw I36. Worm screw I36 engages a member and to a non-rotatable member. worm wheel I38 which is secured to a drive shaft It is a feature of our invention to provide auto- I00 having suitable bearings which will be later matic means to render the latch mechanism indescribed. A worm screw I42 on shaft I40 enoperative when the turret is in a retracted posigages ring gear I22, causing the sleeve I20 to rotate within spider collar I I6. Through the gear These and other objects and advantages of the train thus described, electric motor I is made invention will appear in the following description to rotate sleeve I20. The motor I30 can be reand claims which may best be understood when 30 versed by reversing the field current, thus reconsidered in connection with the accompanyversing the direction of rotation of sleeve I20.

The gear train provides a large reduction in ro- Figure 1 is a side view of an airplane having tation allowing the use of a very high speed a retractable turret mounted in the bottom surmotor, to provide a high power to weight ratio. face thereof, incorporating therein the improve- The column I24, and thereby the turret also, ments according to the present invention; may be rotated in azimuth or retracted and/or Figure 2 is an enlarged part-1y sectional view extended, by selectively connecting column I2 l of the aircraft of Figure 1 in the region of the with sleeve I20 or with non-rotatable head I20. turret showing the turret in an extended or oper- This selective connection is performed by an L- shaped key I44 held in a hole through column I20 Figure 3 is an isometric schematic showing of and selectively engaging an internal notch I50 in the turret in an extended position, partly in secsleeve I20, or an external notch I52 in non-rotattion and showing the mechanical parts and able head I26. The mechanism for moving key I44 will be described later.

Figure 4 is a View in vertical section of the When key I engages notch I52 in non-rotatturret mechanism at the upper end of the central able head I26, column I'M is restrained from rocolumn showing the construction of the retract tation. If motor I30 now rotates ring gear I22,

and thereby sleeve I 20, the column I20 will be Figure 5 is a detail view along the section 5-5 raised or lowered according to the direction of of Figure 4, showing the retract lever in profile. rotation of sleeve I22. The head I26 is lowered Referring now to Figures 1 and 2 there is or raised with column I24, and the yoke member shown an airplane I00 having a turret I 02 there- I28 will telescope and extend and will act at all in which incorporates the improvements formtimes to keep head I26 from rotating. In this 5 way the extension and retraction of turret I02 The mechanical parts relating to the moveis accomplished. When the turret I02 is ex- .sleeve I20 rotates in bearings H8.

tended the key I44 may be moved to engage notch I50 in sleeve I20 and the column I24 will rotate as sleeve I20 rotates, and thus provide the operative movement of rotation in azimuth. It will be noted that in such case the key I44 will be out of notch I52 and there is no restriction on the movement in azimuth. The column I24 can be rotated continuously in either direction for any given number of rotations.

Certain parts of the turret are fastened on the lower end of column I24. These parts include a rotatable shaft I56 to which the guns IIO are secured. A worm wheel sector I60 is secured to shaft I56 and is engaged by a worm screw I62 fastened to a drive shaft I64. Drive shaft I-64 in turn is driven by a worm wheel I66 secured thereto, which is driven by a worm screw I68 secured to a motor shaft I of an electric elevation motor The elevating gear train and its actuating motor are adapted to elevateor depress the guns, depending upon the direction of rotation of motor I12, which is reversed by reversing the'field. The guns IIO can be elevated above horizontal as far as is permitted by the shape of the airplane in which the turret is mounted, and can be depressed to point straight down. The elevation are as will be described for purposes of illustration, will be limited to a 90 are from horizontal to straight down.

The details of the upper end of the central column I24 of the turret are shown in Figure 4. The parts described with reference to diagrammatic sketch Figure 3 are readily distinguishable in Figure 4. Spider II4 supports centralcollar II6 within which internally threaded Ring gear I22 is bolted to sleeve I20 and drives it. Central column I24 is held in threaded sleeve I20 and in this way supports the lower end of the turret. Housing I25 is mounted on spider H4, and encircles ring gear I22 and retains the driving train including worm screw I42 which drives ring gear I22. Housing I25 is sealed to prevent leakage of lubricant and to keep out dirt by an upper annular seal I43 and a lower annular seal I45, both of which are held in casing I25 and wipe a portion of sleev I20 on either side of ring gear I22. Non-rotatable head I26 is held on the top of the column I24 by nut 266.

Figure 4 also shows the mechanism for selectively connecting column I24 to non-rotatable head I26 or to threaded sleeve I20. A recess in the inner side of sleeve I20 near the top forms the notch I50 referred to in Figure 3. An annular end plate I53 having a downwardly projecting flange I53a is screwed to the bottom of non-rotatable head I26. A notch cut in the flange acts as the notch I52 described with reference to Figure 3. A spring pressed button I54 is held in a. recess in the bottom edge of head I26 by end plate I53. However, end plate I53 has an'opening allowing a reduced head of button I54 to protrude therethrough at times. The L-shaped key I44 is fitted into an aperture I55 in column I24. By moving key I44 into sleeve notch I50 or into contact with head notch I52, the column may selectively be rotated, or retracted and/or extended respectively.

The mechanism for moving key I44 is attached to the inside of column I24. At the upper end of column I24a retract lever I46 is mounted on a pivot I41 welded to the inside of column I24. Lever I46 is shown in profile in Figure 5,

where it is shown to be a bent lever pivoted at the bend. The top part of lever I46 projects beyond the top of column I24 where the gunner can manipulate it as desired. The bent end of lever I46 is connected by a link I51 to one end of a .bell crank I56 pivoted on an ear I56 ,welded to column I24. The other end of bell crank I56 is fitted in a slot in connector key I44 and acts against a compression spring I44a to pull the key I44 inward to contact notch I52 in head I26.

In normal operation, spring I44a causes key I 44 to engage notch I50 in sleeve I20, connecting column I24 to sleeve I20. Column I24 (and also bottom part of the turret) will rotate according to the rotation of'sleeve I20. It the gunner should now desire to retract the turret. he rotates the guns to point toward the rear,

bringing the retracting-lever I46 on the forward or gunner side of a periscope tube 306, into a position as shown in Figure 2. While slowly rotating the guns in azimuth toward the rear position, the gunner presses on the lever I46 tending to move key I44 out of sleeve notch I50 and into head notch I52. When key I44 rotates with column I24 to a position opposite notch I52 the key I44 will be able to move into it, stopping the turret from further rotation. Sleeve I20 will continue to rotate, however, and will screw column I24 up into airplane.

When column I24 and head I26 have been retracted a small amount, the head of button I54 will project below end plate I53. If retract lever I46 should now be released, spring I44a would move key I44 outward until it contacted button I54. In this way button I54 acts as a stop for key I44 while the turret is retracted.

If, when the turret is retracted, the gunner wishes to extend it he merely reverses the direction of rotation of azimuth motor I30 from that required to retract the turret, and sleeve I20 will then screw the turret down. As the turret approaches the lower limit of extension, the outer end of key I44 will slide past the upper edge of sleeve I20 because button I54 keeps key I44 within that dimensional limit. At the same time button I54 will contact the top of sleeve I20 and be forced upwardly into its recess. At the lower limit of extension key I44 comes into alignment with notch I50 in sleeve I20 and is snapped into it by the action of spring I44a. Column I24 will then be at its lower limit of extension and will immediately start to rotate and the turret is ready for use.

Having described our invention fully, we do not intend to limit our invention to the embodiments shown or described, nor do w intend to limit our invention in any other way except by the terms of the following claims.

What is claimed is:

1. 'A turret for mounting guns in an airplane, means for extending said turret, means for preventing the extension of said turret beyond predetermined limits and for preventing unintended retraction of said turret comprising a notch, a key movable into said notch, and resilient means for moving said key into said notch whenever said turret is fully extended.

2. In an airplane, a bottom turret comprising a support, a rotatable internally threaded sleeve mounted in said support, a threaded column, a turret mounted on the bottom end of said column, power means to rotate said sleeve, a non-rotatable member adjacent to said column, and locking means on said column to lock said column to said non-rotatable member and to automatically lock said column to said sleeve at the lower limit of extension of said turret.

3. In a gun turret adapted for use in an airplane and of the type which may be extended ior operation or retracted to reduce wind resistance, a support secured to said airplane having an element mounted thereon for rotative and axial ment of said element by the first said means, said" means" including a key and a notch'associate'd with said key for insuring that said element is in proper rotational position before beginning retractive movement.

4. In a turret, a support, an internally threaded sleeve rotatable with respect thereto, a column threaded into said sleeve, a head mounted on said column and non-rotatable with respect to said support and rotatable with respect to said column, a telescoping connection between said support and said head, and means for connecting said column to said head or said sleeve.

5. In a turret, a support, an internally threaded sleeve rotatable with respect thereto and having a notch therein, a column threaded into said sleeve, a head mounted on said column nonrotatable with respect to said support and rotatable with respect to said column and adapted to contactsaid sleeve when the column is moved axially to one extremity of said sleeve, said head having a notch therein, a key held in said column, means to move said key inwardly and outwardly with respect to said column to engage the notch in said head and said sleeve respectively, and means contained within said head adapted to prevent the outward movement of said key while the column is moving axially with respect to said sleeve and adapted to permit the key to move outwardly when the head engages said sleeve whereby the key will engage the notch in said sleeve for rotative movement of said column.

6. In a retractible turret, a support having an element mounted thereon for rotatlve and axial movement with respect thereto, means for effecting rotatlve or axial movement of said element, and means operable to cause rotative movement or axial movement of said element by the first said means, wherein said second named means includes locking means to insure that the element has rotated to a predetermined position with respect to said support before axial movement of the element begins.

7. In a retractible turret, a support having an element mounted thereon for rotative and axial movement with respect thereto, means for eiIecting rotative or axial movement of said element, and means operable to cause rotative movement or axial movement of said element by the first said means, wherein said second named means includes means for precluding axial movement of said element beyond a predetermined limit.

8. A turret, adapted for use in an airplane, comprising a support, a rotatable mounting carried by said support, guns secured to the mounting for movement relative thereto, means for retating said mounting, a well for housing said guns and mounting, means for retracting said guns and mounting into said well, and means comprising a notch and a key for engaging said notch to insure that the guns are properly positioned with respect to said well when said mounting is retracted.

9. A turret, adapted for use in an airplane, comprising a support, a rotatable mounting carried by said support and constructed and arranged to be extended and retracted, guns carried by said mounting, means for rotating said guns and mounting, a well for housing said guns and mounting, means for retracting said guns and mounting into said well, means comprising a notch and a key for engaging said notch to insure that the guns are properly positioned with respect to said well when said turret is retracted, and means for locking said guns against movement in azimuth until said mounting is Iulb extended. 1

GEORGE W. PON'I'IUS. III. ROYAL J. REEK. 

